src/libs/glut/glut_bitmap.c

   1 /*
   2  * Copyright 1994-1997 Mark Kilgard, All rights reserved.
   3  * Distributed under the terms of the MIT License.
   4  *
   5  * GPL licensing not permitted.
   6  *
   7  * Authors:
   8  *      Mark Kilgard
   9  */
  10
  11
  12 #include "glutint.h"
  13 #include "glutbitmap.h"
  14
  15
  16 void APIENTRY
  17 glutBitmapCharacter(GLUTbitmapFont font, int c)
  18 {
  19   const BitmapCharRec *ch;
  20   BitmapFontPtr fontinfo;
  21   GLint swapbytes, lsbfirst, rowlength;
  22   GLint skiprows, skippixels, alignment;
  23
  24 #if defined(_WIN32)
  25   fontinfo = (BitmapFontPtr) __glutFont(font);
  26 #else
  27   fontinfo = (BitmapFontPtr) font;
  28 #endif
  29
  30   if (c < fontinfo->first ||
  31     c >= fontinfo->first + fontinfo->num_chars)
  32     return;
  33   ch = fontinfo->ch[c - fontinfo->first];
  34   if (ch) {
  35     /* Save current modes. */
  36     glGetIntegerv(GL_UNPACK_SWAP_BYTES, &swapbytes);
  37     glGetIntegerv(GL_UNPACK_LSB_FIRST, &lsbfirst);
  38     glGetIntegerv(GL_UNPACK_ROW_LENGTH, &rowlength);
  39     glGetIntegerv(GL_UNPACK_SKIP_ROWS, &skiprows);
  40     glGetIntegerv(GL_UNPACK_SKIP_PIXELS, &skippixels);
  41     glGetIntegerv(GL_UNPACK_ALIGNMENT, &alignment);
  42     /* Little endian machines (DEC Alpha for example) could
  43        benefit from setting GL_UNPACK_LSB_FIRST to GL_TRUE
  44        instead of GL_FALSE, but this would require changing the
  45        generated bitmaps too. */
  46     glPixelStorei(GL_UNPACK_SWAP_BYTES, GL_FALSE);
  47     glPixelStorei(GL_UNPACK_LSB_FIRST, GL_FALSE);
  48     glPixelStorei(GL_UNPACK_ROW_LENGTH, 0);
  49     glPixelStorei(GL_UNPACK_SKIP_ROWS, 0);
  50     glPixelStorei(GL_UNPACK_SKIP_PIXELS, 0);
  51     glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
  52     glBitmap(ch->width, ch->height, ch->xorig, ch->yorig,
  53       ch->advance, 0, ch->bitmap);
  54     /* Restore saved modes. */
  55     glPixelStorei(GL_UNPACK_SWAP_BYTES, swapbytes);
  56     glPixelStorei(GL_UNPACK_LSB_FIRST, lsbfirst);
  57     glPixelStorei(GL_UNPACK_ROW_LENGTH, rowlength);
  58     glPixelStorei(GL_UNPACK_SKIP_ROWS, skiprows);
  59     glPixelStorei(GL_UNPACK_SKIP_PIXELS, skippixels);
  60     glPixelStorei(GL_UNPACK_ALIGNMENT, alignment);
  61   }
  62 }